Abstract: To investigate the mechanism of drug resistance of fowl E.coli biofilm,the in vitro model of fowl E.coli biofilm was established with the improved flat-board method,and the sensitivity of biofilm,the planktonic and the defilming to thirteen antibacterial agents(including clarithromycin,ciprofloxacin,fosfomycin,etc.)were determinded by broth double dilution.Meanwhile,ESBLs production was also detected.The result revealed that the planktonic and the defilming had the similar antibiotic susceptibilities,while the biofilm was significantly higher than those above two.Two planktonic non-ESBLs strains could produce ESBLs after becoming biofilm.All these proved that the special structure of biofilm is the fundamental factor of drug resistance of bacterial biofilm,and the existence of biofilm enhances the production of ESBLs.It was concluded that the formation of biofilm and the production of ESBLs are the two key reasons for drug resistance of the fowl E.coli biofilm.

Key words: Fowl E. coli, Biofilm, Drug resistance, ESBLs

CLC Number: 

• S859